On Thu, 30 Apr 2020, luoxhu wrote:
> Update the patch with overflow check. Bootstrap and regression tested PASS
> on Power8-LE.
>
>
> Use determine_value_range to get value range info for fold convert expressions
> with internal operation PLUS_EXPR/MINUS_EXPR/MULT_EXPR when not overflow on
> wrapping overflow inner type. i.e.:
>
> (long unsigned int)((unsigned int)n * 10 + 1)
> =>
> (long unsigned int)n * (long unsigned int)10 + (long unsigned int)1
>
> With this patch for affine combination, load/store motion could detect
> more address refs independency and promote some memory expressions to
> registers within loop.
>
> PS: Replace the previous "(T1)(X + CST) as (T1)X - (T1)(-CST))"
> to "(T1)(X + CST) as (T1)X + (T1)(CST))" for wrapping overflow.
This is OK for trunk if bootstrapped / tested properl.
Thanks,
Richard.
> gcc/ChangeLog
>
> 2020-04-30 Xiong Hu Luo <luo...@linux.ibm.com>
>
> PR tree-optimization/83403
> * tree-affine.c (expr_to_aff_combination): Replace SSA_NAME with
> determine_value_range, Add fold conversion of MULT_EXPR, fix the
> previous PLUS_EXPR.
>
> gcc/testsuite/ChangeLog
>
> 2020-04-30 Xiong Hu Luo <luo...@linux.ibm.com>
>
> PR tree-optimization/83403
> * gcc.dg/tree-ssa/pr83403-1.c: New test.
> * gcc.dg/tree-ssa/pr83403-2.c: New test.
> * gcc.dg/tree-ssa/pr83403.h: New header.
> ---
> gcc/testsuite/gcc.dg/tree-ssa/pr83403-1.c | 8 ++++++
> gcc/testsuite/gcc.dg/tree-ssa/pr83403-2.c | 8 ++++++
> gcc/testsuite/gcc.dg/tree-ssa/pr83403.h | 30 +++++++++++++++++++++++
> gcc/tree-affine.c | 24 ++++++++++--------
> 4 files changed, 60 insertions(+), 10 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr83403-1.c
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr83403-2.c
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr83403.h
>
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr83403-1.c
> b/gcc/testsuite/gcc.dg/tree-ssa/pr83403-1.c
> new file mode 100644
> index 00000000000..748375b03af
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr83403-1.c
> @@ -0,0 +1,8 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O3 -funroll-loops -fdump-tree-lim2-details" } */
> +
> +#define TYPE unsigned int
> +
> +#include "pr83403.h"
> +
> +/* { dg-final { scan-tree-dump-times "Executing store motion of" 10 "lim2" }
> } */
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr83403-2.c
> b/gcc/testsuite/gcc.dg/tree-ssa/pr83403-2.c
> new file mode 100644
> index 00000000000..ca2e6bbd61c
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr83403-2.c
> @@ -0,0 +1,8 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O3 -funroll-loops -fdump-tree-lim2-details" } */
> +
> +#define TYPE int
> +
> +#include "pr83403.h"
> +
> +/* { dg-final { scan-tree-dump-times "Executing store motion of" 10 "lim2" }
> } */
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr83403.h
> b/gcc/testsuite/gcc.dg/tree-ssa/pr83403.h
> new file mode 100644
> index 00000000000..0da8a835b5f
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr83403.h
> @@ -0,0 +1,30 @@
> +__attribute__ ((noinline)) void
> +calculate (const double *__restrict__ A, const double *__restrict__ B,
> + double *__restrict__ C)
> +{
> + TYPE m = 0;
> + TYPE n = 0;
> + TYPE k = 0;
> +
> + A = (const double *) __builtin_assume_aligned (A, 16);
> + B = (const double *) __builtin_assume_aligned (B, 16);
> + C = (double *) __builtin_assume_aligned (C, 16);
> +
> + for (n = 0; n < 9; n++)
> + {
> + for (m = 0; m < 10; m++)
> + {
> + C[(n * 10) + m] = 0.0;
> + }
> +
> + for (k = 0; k < 17; k++)
> + {
> +#pragma simd
> + for (m = 0; m < 10; m++)
> + {
> + C[(n * 10) + m] += A[(k * 20) + m] * B[(n * 20) + k];
> + }
> + }
> + }
> +}
> +
> diff --git a/gcc/tree-affine.c b/gcc/tree-affine.c
> index 0eb8db1b086..5620e6bf28f 100644
> --- a/gcc/tree-affine.c
> +++ b/gcc/tree-affine.c
> @@ -343,24 +343,28 @@ expr_to_aff_combination (aff_tree *comb, tree_code
> code, tree type,
> wide_int minv, maxv;
> /* If inner type has wrapping overflow behavior, fold conversion
> for below case:
> - (T1)(X - CST) -> (T1)X - (T1)CST
> - if X - CST doesn't overflow by range information. Also handle
> - (T1)(X + CST) as (T1)(X - (-CST)). */
> + (T1)(X *+- CST) -> (T1)X *+- (T1)CST
> + if X *+- CST doesn't overflow by range information. */
> if (TYPE_UNSIGNED (itype)
> && TYPE_OVERFLOW_WRAPS (itype)
> - && TREE_CODE (op0) == SSA_NAME
> && TREE_CODE (op1) == INTEGER_CST
> - && icode != MULT_EXPR
> - && get_range_info (op0, &minv, &maxv) == VR_RANGE)
> + && determine_value_range (op0, &minv, &maxv) == VR_RANGE)
> {
> + wi::overflow_type overflow = wi::OVF_NONE;
> + signop sign = UNSIGNED;
> if (icode == PLUS_EXPR)
> - op1 = wide_int_to_tree (itype, -wi::to_wide (op1));
> - if (wi::geu_p (minv, wi::to_wide (op1)))
> + wi::add (maxv, wi::to_wide (op1), sign, &overflow);
> + else if (icode == MULT_EXPR)
> + wi::mul (maxv, wi::to_wide (op1), sign, &overflow);
> + else
> + wi::sub (minv, wi::to_wide (op1), sign, &overflow);
> +
> + if (overflow == wi::OVF_NONE)
> {
> op0 = fold_convert (otype, op0);
> op1 = fold_convert (otype, op1);
> - return expr_to_aff_combination (comb, MINUS_EXPR, otype,
> - op0, op1);
> + return expr_to_aff_combination (comb, icode, otype, op0,
> + op1);
> }1
> }
> }
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)
